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<title>Traditional Mode (The C Preprocessor)</title>

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<h2 class="chapter" id="Traditional-Mode-1"><span>10 Traditional Mode<a class="copiable-link" href="#Traditional-Mode-1"> &para;</a></span></h2>

<p>Traditional (pre-standard) C preprocessing is rather different from
the preprocessing specified by the standard.  When the preprocessor 
is invoked with the 
<samp class="option">-traditional-cpp</samp> option, it attempts to emulate a traditional
preprocessor.  
</p>
<p>This mode is not useful for compiling C code with GCC, 
but is intended for use with non-C preprocessing applications.  Thus
traditional mode semantics are supported only when invoking
the preprocessor explicitly, and not in the compiler front ends.
</p>
<p>The implementation does not correspond precisely to the behavior of
early pre-standard versions of GCC, nor to any true traditional preprocessor.
After all, inconsistencies among traditional implementations were a
major motivation for C standardization.  However, we intend that it
should be compatible with true traditional preprocessors in all ways
that actually matter.
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<li><a href="Traditional-lexical-analysis.html" accesskey="1">Traditional lexical analysis</a></li>
<li><a href="Traditional-macros.html" accesskey="2">Traditional macros</a></li>
<li><a href="Traditional-miscellany.html" accesskey="3">Traditional miscellany</a></li>
<li><a href="Traditional-warnings.html" accesskey="4">Traditional warnings</a></li>
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